Best Blog Writing?

What is the best way to blog?
I have only just asked myself this question - and I am not sure I have any answers. At Manaia Kindergarten we blog as we would a daily diary - I guess you could call this the traditional way of blogging and it works well in a kindergarten setting, with the goals of informing parents about the daily/weekly learning experiences that take place at Kindergarten.
But what about professional blogs? As I have mentioned before I have a raft of unpublished (incomplete) blog posts. With a combination of writer's block followed by an onslaught of bloggable thoughts from various sources, I find my blog is feeling my blog posts are rather 'random'. It doesn't seem that my ideas are related or continue from one day to the next. Rather it seems like haphazardly inspired thoughts explored, analysed , written and abandoned. Followed by another random thought. Yes the thoughts may have something of value on their own - but is it best to have one's ideas following a logical pattern? Would that mean more to readers, would they read more posts, and therefor be more involved as a result of time spent on a blog? Or are today's readers more interested in one off blog posts, quick sources of information/discussion? Jumping from Google search to google search?

So - time to consider some organisation of this blog? limits to themes/ideas? a more narrowly defined thread?